In search of my next adrenaline rush, I wondered if swapping the engine on my ATV would allow me to boost my ATV, with all its upgrades, instead of having to buy a new machine. Vehicle modifications can be complicated, so I wanted to make sure that I knew precisely what I could and could not do before starting on any costly changes.
So, can you swap your ATV’s engine? Swapping ATV engines is actually common practice with professional riders and casual enthusiasts alike. An engine swap can boost performance and yield benefits, including:
- Increased horsepower
- More dependability
- Improved fuel efficiency
With summer coming to an end, now is a fitting time to modify your ATV and get it ready for the next riding season. Here’s everything you need to know before you make the swap.
Why You Would Swap Your ATV’s Engine
EPA emission regulations include ATV engines. To meet those standards, most manufacturers do not optimize their vehicles’ performance.
Whether you are looking to bulk up for an upcoming race or create a smoother ride for leisurely travel, performing an engine swap may help ensure your ATV meets your needs. Below are some reasons why swapping your ATV’s engine may be the right move for you.
More Power and More Speed.
Recreational ATVs can have more than 50 horsepower, and racing ATVs reach top-speeds of up to 89 mph. When you first purchase an ATV from a manufacturer, there are often restrictors in place, such as limiters, that keep your speed in check.
While going fast may give you a rush, modifying your engine for increased horsepower will lower its lifespan. You will likely need to replace or repair it sooner than you would with the original specifications.
That is why engine swaps are more common among ATV racers. When you run your engine hard, you will wear it out sooner and need to swap it out for a new engine to keep it going.
New Rider on the ATV
When it comes to ATVs, one size does not fit all. The type of engine you use greatly impacts an ATV’s handling and usability. An engine swap is a potentially smart option—particularly if an ATV changes from expert to novice hands or vice versa. Just as you might swap parts for various purposes, you may want a different engine that better suits the rider.
Your Engine Crapped Out On You
Due to negligence or just lots of wear, engines can become damaged and need replacement. Examples of improper care include:
- Never cleaning the air filter
- Neglecting to change the oil
- Submerging the engine in water
- Riding with a clogged radiator
Like most mechanical parts, engines also experience normal wear and tear too. If you have had your ATV for a while or recently purchased one used, swapping out the engine can save an otherwise good ATV.
Top 3 Factors to Consider When Swapping an ATV’s Engine
ATVs can cost anywhere from a few thousand dollars to over $15,000, so you will want to do your due diligence before swapping a major piece. Here are the aspects you should consider when purchasing your new engine.
1. Safety
Handling an ATV takes a certain amount of body weight and physical strength, which varies from rider to rider. The size of the ATV and power of the engine should be matched to the specifications of the rider. Otherwise, you run the risk of not being able to control the vehicle. The ideal quad for an experienced and fit professional differs from a machine built for a child just learning to ride.
If you need help figuring out what size engine is best for you, check out our handy guide to picking the right size ATV.
2. Stroke
ATVs use two types of engines: two-stroke and four-stroke. There are passionate advocates for both, but two-stroke engines are no longer manufactured and typically only found in older machines. Therefore, you can only purchase used two-stroke engines.
The main difference between the two is that a 2 stroke engine can produce more torque at higher RPM, but requires you to mix an oil and fuel combination. On the other hand, 4 stroke engines create a higher torque at lower RPM. The 4 stroke engine is also much heavier.
The number of strokes refers to how many rotations the piston needs to complete the power cycle. If you want to learn more about how an ATV engine works, watch this quick video.
Enough with how they work, which engine is better? There are benefits to both engines, and my advice is that you figure out which one best suits your needs. Two-stroke engines are superior for speed and personalization, while four-stroke engines typically require less maintenance and run cleaner. Here is a side by side comparison of the pros and cons of each engine type:
| 2-Stroke Engine | 4-Stroke Engine |
| Harder to control, requires an experienced rider | Easier to control, better for beginners |
| Better for speed | Better for comfort |
| Simple design, no oil reservoir—Lighter | Complicated design, oil reservoir—Heavier |
| Lower fuel efficiency | Higher fuel efficiency |
| Less power (per RPMs) | More power (per RPMs) |
| Faster acceleration and deceleration | Slower acceleration and deceleration |
| Cheaper to maintain and repair, but faster wear and tear | More expensive to maintain and repair, but slower wear and tear |
| Fewer moving parts | More moving parts |
| Harder on the environment | Easier on the environment |
| Easier to self-repair | Harder to self-repair |
3. Compatibility
Unless you are looking to replace additional parts on your ATV, whatever engine you are swapping to must be compatible with the rest of your quad. Engine sizes can range from 49 to 1,000 ccs, and a four-stroke engine is up to 50% heavier than a comparable two-stroke engine. Swapping to a larger or heavier engine will require a bigger and sturdier frame to deal with the added weight.
Self vs. Shop Installation
Once you decide to swap your engine, you can do it yourself or take it to a shop at your convenience.
If you are a hobbyist looking for a side-project, swapping an engine can be a fun, albeit challenging, experience. You might even save a little money, though keep in mind that the job will likely require special tools.
There are plenty of resources online, including forums where users share their builds and offer each other advice. A lot of motor enthusiasts also like to document their swaps on YouTube.
ATV modifications can be complicated and increasingly complex, depending on what you are trying to do. There is no shame in saving yourself the headache and hiring a professional. Often, shops will perform additional services such as engine inspection and dyno tuning. They can also answer any questions you may have about maintaining your new engine.
The cost of an engine swap is going to vary quite a bit among different locations and mechanics so we can’t give you helpful advice on the price.; however, to learn more about what mechanics charge for most ATV repairs versus doing it yourself, look at this guide.
Other Ways to Improve Your ATV’s Performance
While the most grand, swapping the engine is not the only way to increase the performance of your ATV. In fact, there are plenty of easier (and often cheaper!) ways to get the extra kick you are looking for.
- Using high-quality fuel. As with all vehicles, higher octane gasoline will burn more efficiently and improve performance.
- Cleaning the air filter. The purpose of the air filter is to maximize the amount of air that goes into the combustion chamber of the engine. To maintain optimum performance, make sure that you keep your air filter free from impurities such as mud, rocks, and sticks.
- Adjusting your tires and tire pressure. Increased traction will improve the performance of your tires as well as the handling and speed capabilities of your ATV. The more tread that is in contact with the ground at any given point, the better traction you will have.
- Gearing up or down. Gearing up or down consists of either adding or removing teeth to your rear and front sprockets. If you want higher top-end speeds and do not mind poorer acceleration, then consider gearing up. To get more acceleration at the cost of lower top-end speed, gear down.
If you want more ideas, be sure to check out this helpful guide on increasing the torque and horsepower in an ATV.
Modifying an Engine With a Bore Kit
If you are looking for a simpler and cheaper way to power up your 4×4, consider buying a bore kit. A bore kit replaces the stock piston and cylinder bore with a larger version, increasing combustion flow and torque. Keep in mind that installing a bore kit also increases the engine size. You can find bore kits on Amazon, ranging from less than $50 to several hundred dollars.
Conclusion
If you have decided swapping your ATV’s engine is the right move, Good Luck! It really isn’t as difficult as you would imagine, but be sure to do the research and get help if you need it. If swapping your engine isn’t right for you, try out some of the other options we discussed and give your ATV that added boost you are looking for!
